A fully charged capacitor has a capacitance ‘$C$ ’. It is discharged through a small coil of resistance wire embedded in a thermally insulated block of specific heat capacity ‘$s$ ’ and mass ‘$m$ ’. If the temperature of the block is raised by ‘$\Delta T$ ’, the potential difference $V$ across the capacitance is:

1. A
   $\sqrt{\frac{2mC\Delta T}{s}}$
2. B
   $\frac{mC\Delta T}{s}$
3. C
   $\sqrt{\frac{ms\Delta T}{C}}$
4. D
   $\sqrt{\frac{2ms\Delta T}{C}}$